a law enforcement official tells cnn investigators are looking into how the perpetrators got the data and whether it was hacked or not. the fbi, secret service and los angeles police are all on their trail. i spoke with michael gibbons, former head of the fbi's computer investigation's unit. >> how are investigators tracking these suspects? >> the addresses of computers will lead you to other computers and little detail file names and snippets of file and computer systems looking for an exact piece of evidence from across the globe. >> reporter: two credit agencies confirm information on their clients was accessed. how easy is it for an impersonator to fake an inquiry and get data about you from a credit agency? i called for a free credit report to learn the type of information they ask for. my mailing address is -- [ bleep ]. my social security number is -- just hung up with annualcreditreport.com. they asked for my full name, mailing address, and social security number. for that they did offer a security safe guard asking if i only wanted my last four digits posted with my report. o